Tondo is a Renaissance term for a circular painting. To create my floral tondo, I started with a circular pattern on my light box. I arranged an array of petals—mostly alstromeria but also some rose petals and Agapanthus blossoms—around the central core of a rose. I then photographed the composition for transparency (see my FAQ for more info on this technique).
In post-production, after processing my high-key layer stack, I added a black background to emphasize the tondo effect, and used the Warp transform in Photoshop to make the flowers seem to slightly wrap around the white space created by the circular background.